Linkfix as shape() moved from Shapes 2 to Shapes 1. Fix w3c/fxtf-drafts#598

Author: svgeesus

motion-1/Overview.bs

@@ -30,6 +30,8 @@ spec: css-backgrounds-3;  type:property;
     text: border-radius
 spec:motion-1; type:value; 
     text:path()
+spec:css-shapes-1; type:dfn;
+    text:shape()
 </pre>